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Lee, A. Bolles.

Poppius, Alfred.

Comstock, J. H.

Brauer, F.

Brauer, F., und J. Redtenbacher.

Redtenbacher, J.

Schoch, G.

Bondsdorff, A.

Spuler, Arnold.

Also the writings of Adolph, Bugnion, Calvert, Comstock, Diez, Giraud, Gonin, Graber, Kellogg, Packard, Pratt, Scudder, Walsh.

Marey’s views on the flight of insects.

Fig. 163.—The two upper lines are produced by the contacts of a drone’s wing on a smoked cylinder. In the middle are recorded the vibrations of a tuning-fork (250 vibrations per second) for comparison with the frequency of the wing movements. Below are seen the movements of the wing of a bee.—After Marey.

If we take off the wing of an insect, and holding it by the small joint which connects it with the thorax, expose it to a current of air, we see that the plane of the wing is inclined more and more as it is subjected to a more powerful impulse of the wind. The anterior nervure resists, but the membranous portion which is prolonged behind bends on account of its greater pliancy.